This synopsis supplement reports advances and key observations that will affect the care of children with allergic and immunologic diseases now and in the near future. Reviewers for the synopsis supplement selected many articles that have clinical “pearls” and provide insights that are applicable for daily practice. For example, although there have been studies that support the “hygiene hypothesis,” that reduced infection has led to increased atopic disease, 2 studies reported this year did not show that antibiotic use per se is related to increased atopic outcomes. Curiously, 1 large study showed an association of atopy with use of acetaminophen, but additional prospective studies are needed. Also reported is a study that showed that obesity may increase the risk of atopic disease, providing further fuel to address the obesity epidemic. The efficacy of atopy prevention with probiotics continues to remain uncertain, with studies on both sides. Adding to data that do not support prolonged elimination of dietary allergens (eg, beyond 6 months) as a means for atopy prevention, a study that showed worse atopic dermatitis outcomes when milk protein introduction was delayed is reported. Another observation against prolonged food allergen avoidance as a prevention strategy is from a study that showed that peanut allergy is more common in Jewish children surveyed in the United Kingdom, where introduction of peanut is typically delayed, compared with Israel, where it is ingested more typically in the first year of life. However, randomized trials are still needed to determine the impact of timing of allergen ingestion on atopy outcomes. Regarding treatment of food allergy, a randomized, controlled trial of milk oral immunotherapy showed that treated subjects were able to significantly increase the amount of milk they could ingest. Although this is exciting and promising, additional studies are needed to characterize the safety and efficacy of the approach and also to determine whether the treatment induces a permanent cure or only an increased threshold during treatment. Additional observations regarding food allergy include reports of the utility of serum immunoglobulin E tests for diagnosing peanut, tree nut, and soy allergy. Several studies selected by our reviewers characterized eosinophilic esophagitis, which seems to be a persistent illness that should be considered in young children with atopy and gastrointestinal symptoms such as reflux and failure to thrive and in older children with reflux symptoms and dysphagia. Another gastrointestinal food-allergic disease being increasingly well characterized is food protein-induced enterocolitis syndrome, a disorder with severe vomiting and possible hypotension; symptoms begin ∼2 hours after ingestion of the causal protein. Several articles on this topic have underscored the need for a high index of suspicion to avoid misdiagnosis, including appreciation that the illness is not associated with positive allergy tests for the trigger foods and that reactions mimic sepsis. Several studies have addressed the clinical management of atopic dermatitis, with emphasis on the etiologic role of bacteria, potential efficacy of measures to reduce skin infection such as “bleach baths,” and preemptive therapies rather than reactionary treatment. Numerous insights about asthma have also been reported. For example, 2 studies specifically documented improved asthma when exposure to environmental tobacco smoke and to pollution is reduced. The interrelationship of viral infections and risks of asthma/allergy has been explored in epidemiological and laboratory studies; for example, in a murine study, there was increased susceptibility to allergen sensitization with acute influenza A infection. Several studies explored approaches to using antiinflammatory medications for asthma, intermittently, regularly, or presymptomatically (eg, in response to viral infection). Although the results are preliminary, the observations from these studies provide interesting insights about relative risks/benefits of these approaches. Several studies evaluated the safety and efficacy of noninjection routes of allergen immunotherapy, by using oral or sublingual administration, with promising results. In the field of primary immunodeficiency, dissection of the molecular basis of these myriad disorders continues with identification of infection outcomes for those with myeloid differentiation protein 88 (MyD88) deficiency. In addition, a study showed promising long-term outcomes for gene therapy treatment of adenosine deaminase deficiency. Immunologic studies are identifying new potential means of reducing HIV transmission and replication, and several medical therapies have shown promise for controlling HIV infection.
On behalf of myself and our reviewers, we hope that this supplement stimulates and informs, giving you practical information to improve the care of children with allergic and immunologic diseases now and an exciting peek out the window toward understanding therapies on the horizon. For additional information about our Section, please visit www.aap.org/sections/allergy.
- Copyright © 2009 by the American Academy of Pediatrics